We propose to establish a Health Sciences Informatics Training Program at Johns Hopkins for health professionals and others with information or computer science backgrounds, with a special track for librarians. This postgraduate certificate program, to be housed in the School of Medicine's Division of Biomedical Information Sciences, is based on the premise that "health sciences" comprises biological, clinical, and public health domains and that there are core sets of knowledge and skills that generalize across these informatics domains. It embodies our conviction that training for a future in health sciences informatics research requires a mentored research experience and exposure to a range of real-world problems in these health science domains. Given the richly diverse set of research and informatics opportunities available at Johns Hopkins, we believe that our collaborative model, which reaches across all of the schools in the University, can serve as the basis for an effective multidisciplinary program. The educational goals of the proposed 2-year curriculum are to: 1) bring trainees to a baseline level of competency in health sciences informatics; 2) impart the fundamentals of health sciences informatics research; 3) help trainees to develop proficiency in one or more defined areas of health sciences informatics; 4) provide opportunities to increase their knowledge of fields related to health sciences informatics, such as computer science, biostatistics, and evaluation methodology; 5) provide opportunities to observe and participate in collaborative research and development activities in health sciences informatics; 6) provide a health informatics research experience that includes proposal development, project execution, and evaluation and reporting of results. The proposed multidisciplinary program will include faculty from throughout the University. The curriculum will incorporate the following components: 1) enabling knowledge and skills; 2) core knowledge and skills, 3) practical experience through informatics clerkships, and 4) mentored research. The informatics clerkships, a novel component of our program, will involve 2-month rotations in one of the many relevant laboratories, research cores, data centers, and development shops associated with the University, and particularly the Schools of Medicine, Public Health, and Nursing. Mentoring for research will involve the core faculty working with other affiliated faculty. The success of the program will be assessed, formatively, through the quality of students attracted, the performance and publications of the trainees, and their professional achievements after leaving the program.